Phytochemical investigations and evaluation of antidiabetic potential of Prunus dulcis nuts

Phytochemical Profiling and Biological Potential of Prunus dulcis Shell Extracts

Prunus dulcis is one of the most widely cultivated species in the world. Its fruit (almond) is rich in various nutritious and bioactive compounds that exert several beneficial effects. The aim of this study was to determine the chemical profile and evaluate the biological potential in vitro of almond shell extracts. The chemical analysis of shell extracts led to the identification of 15 compounds by HPLC-DAD, of which 11 were first detected in the almond plant. Twenty-six volatile compounds were identified by the GC-MS technique; among them, seven were firstly detected in the studied plant. For the biological activities, the extracts demonstrated moderate inhibition potential against the antioxidant, antidiabetic, and cytotoxic activities. The methanol extract at 50 µg/mL showed the highest antioxidant (45%) and antidiabetic activities (45% against alpha-glucosidase and 31% against alpha-amylase extracts), while the cyclohexane and dichloromethane at 50 µg/mL showed the highest cytotoxic activity towards Hela (32.2% with cyclohexane) and RAW 264-7 (45% with dichloromethane). Overall, these findings demonstrate the potential of almond shell extracts as a source of bioactive compounds that could be applied in the pharmaceutical and medical fields.

The Beekeeping State and Inventory of Mellifero-Medicinal Plants in the North-Central of Morocco

This study aims to determine the diversity of melliferous plants and to recognize the state of beekeeping in the Fez-Meknes region in Morocco. We conducted a questionnaire for beekeepers that set up their hives in the prefectures and provinces of the region, and we have studied the pharmacological evidence of the most preferred plants by beekeepers to assess its medicinal values. The results indicate that honey, bee pollen, bee bread, royal jelly, propolis, bee wax, bee venom, and bee queens are produced in this region with different percentages, and 102 plants belonging to 32 families were obtained in the inventory of melliferous plants; the most represented families were Asteraceae and Lamiaceae (13.73% each) followed by Rosaceae (8.82%). Among these 102 plants identified, 79 plants provide nectar and pollen for bees, 16 plants provide only pollen, 3 plants provide only nectar, 35 plants are resinous, and 6 plants provide honeydew for bees. The outcome of this study will contribute to the valuation of melliferous plants and help to establish a practical guide for the development of the beekeeping sector as an agricultural economic approach.

Review about Non-Lipid Components and Minor Fat-Soluble Bioactive Compounds of Almond Kernel

This work presents a bibliographic review about almond kernel non-lipid components, in particular about the protein fraction, the carbohydrates and the mineral fraction. In addition, other fat-soluble phytochemicals which are present in minor concentrations but show important antioxidant activities are reviewed. Almond kernel is a rich protein food (8.4-35.1%), in which the globulin-albumin fraction dominates, followed by glutelins and prolamins. Within the almond kernel protein profile, amandine dominates. Free amino acids represent a small amount of the total nitrogen quantity, highlighting the presence of glutamic acid and aspartic acid, followed by arginine. Carbohydrates that appear in almond kernels (14-28%) are soluble sugars (mainly sucrose), starch and other polysaccharides such as cellulose and non-digestible hemicelluloses. Regarding the mineral elements, potassium is the most common, followed by phosphorus; both macronutrients represent more than 70% of the total mineral fraction, without taking into account nitrogen. Microminerals include sodium, iron, copper, manganese and zinc. Within the phytochemical compounds, tocopherols, squalene, phytosterols, stanols, sphingolipids, phospholipids, chlorophylls, carotenoids, phenols and volatile compounds can be found.

Ethnopharmacological review of medicinal plants used to manage diabetes in Morocco

Diabetes is a chronic metabolic disorder which affects millions of people every year. If diabetes is not controlled, it can cause serious damage and a number of health complications. The aim of this paper was to review published ethnobotanical and ethnopharmacological evidences of Moroccan plants with antidiabetic potentials. Publications describing the medicinal plants used for the treatment of diabetes in Morocco were searched from the databases, including Google Scholar, Elsevier, Medline, Web of Science, SCOPUS and Pubmed. Other literature source was also used including books and theses available in library. About 750 literature references were studied, and only 240 research publications based on data from different Moroccan provinces published until June 2019 were included in this review. In total, 255 plants species belonging to 70 families were reported. Compositae and Lamiaceae were mentioned as the most represented families. The frequently used plant species in the dwellers of most regions of Morocco are Trigonella foenum-graecum, Artemesia herba-alba, Nigella sativa, Olea europaea, Allium cepa and Marrubium vulgare. This review provides useful information and current scientific knowledge on the medicinal plants used to manage diabetes in Morocco. Medicinal plants reported should be submitted to chemical, pharmacological and clinical studies to identify pharmacologically active metabolites and to confirm their antidiabetic activity.

Chemical and Pharmacological Evaluation of Hulls of Prunus dulcis Nuts

Researchers have shown that the almond hulls, normally wasted after utilization of nuts, contain a number of biologically active compounds based on which the present study has been carried out. Focus is placed on the mass spectrometric determination of the analytes along with the estimation of total polyphenolic and total flavonoid contents in the 70% ethanol extract. After partitioning the 70% ethanol extract in hexane, chloroform, ethyl acetate, n-butanol, and water, all the extracts were evaluated for their antioxidant, antidiabetic, and antimicrobial activities. The results delivered total polyphenolic compounds as gallic acid equivalents (1% w/w) of the dried extract and total flavonoid contents as quercetin equivalents (0.2% w/w) of the dried extract. Mass spectrometric analysis resulted in the identification of 15 compounds containing various derivatives of (epi)catechin, chlorogenic acid, kaempferol, isorhamnetin and their glycosides, ursolic acid, amygdalactone, and benzoic acid derivatives. Antioxidant activity experiments showed that highest activity was found in n-butanol extract among the studied samples with IC₅₀ value as 76.04 μg/ml, while hexane and chloroform extracts were active against the PTP1B enzyme with IC₅₀ values 9.66 μg/ml and 37.95 μg/ml, respectively. Hexane and chloroform fractions were active against Staphylococcus aureus with the zone of inhibition diameter 9 mm and 12 mm, respectively.

Cosmetic potentials of Prunus domestica L. leaves

BACKGROUND

The current study presents new insight on the phytochemical content and biological activities of five Prunus domestica L. varieties ('Quetsche blanche de Létricourt', 'Mirabelle de Nancy', 'Perdrigon violet', 'Mirabelle de Provence', 'Reine-claude dorée').

RESULTS

The plum leaves were found to possess promising anti-aging activities by their capacity to inhibit 1,1-diphenyl-2-picrylhydrazyl (DPPH), elastase, hyaluronidase and lipoxygenase. After solid phase extraction (SPE), chlorogenic acid, rutin, quercetin and their derivatives were putatively identified by high-performance liquid chromatography coupled with tandem mass spectrometry using an electrospray ionization source (HPLC/ESI-MS/MS).

CONCLUSION

The plum leaf, a by-product, provides an interesting valuable resource for use as a natural cosmetic product or as a food supplement. © 2017 Society of Chemical Industry.

Protein tyrosine phosphatase 1B inhibitors from natural sources

Since PTP1B enzyme was discovered in 1988, it has captured the research community's attention. This landmark discovery has stimulated numerous research studies on a variety of human diseases, including cancer, inflammation, and diabetes. Tremendous progress has been made in finding PTP1B inhibitors and exploring PTP1B regulatory mechanisms. This review investigates for the natural PTP1B inhibitors, and focuses on the common characteristics of the discovered structures and structure-activity relationships. To facilitate understanding, all the natural compounds are here divided into five different classes (fatty acids, phenolics, terpenoids, steroids, and alkaloids), according to their skeletons. These PTP1B inhibitors of scaffold structures could serve as a theoretical basis for new concept drug discovery and design.

Evaluation of the Antidiabetic Activity and Chemical Composition of Geranium collinum Root Extracts-Computational and Experimental Investigations

The root of Geranium collinum Steph is known in Tajik traditional medicine for its hepatoprotective, antioxidant, and anti-inflammatory therapeutic effects. The present study was conducted to evaluate of potential antidiabetic, antioxidant activities, total polyphenolic and flavonoid content from the different extracts (aqueous, aqueous-ethanolic) and individual compounds isolated of the root parts of G. collinum. The 50% aqueous-ethanolic extract possesses potent antidiabetic activity, with IC₅₀ values of 0.10 μg/mL and 0.09 μg/mL for the enzymes protein-tyrosine phosphatase (1B PTP-1B) and α-glucosidase, respectively. Phytochemical investigations of the 50% aqueous-ethanolic extract of G. collinum, led to the isolation of ten pure compounds identified as 3,3',4,4'-tetra-O-methylellagic acid (1), 3,3'-di-O-methylellagic acid (2), quercetin (3), caffeic acid (4), (+)-catechin (5), (-)-epicatechin (6), (-)-epigallocatechin (7), gallic acid (8), β-sitosterol-3-O-β-d-glucopyranoside (9), and corilagin (10). Their structures were determined based on 1D and 2D NMR and mass spectrometric analyses. Three isolated compounds exhibited strong inhibitory activity against PTP-1B, with IC₅₀ values below 0.9 μg/mL, more effective than the positive control (1.46 μg/mL). Molecular docking analysis suggests polyphenolic compounds such as corilagin, catechin and caffeic acid inhibit PTP-1B and β-sitosterol-3-O-β-d-gluco-pyranoside inhibits α-glucosidase. The experimental results suggest that the biological activity of G. collinum is related to its polyphenol contents. The results are also in agreement with computational investigations. Furthermore, the potent antidiabetic activity of the 50% aqueous-ethanolic extract from G. collinum shows promise for its future application in medicine. To the best of our knowledge, we hereby report, for the first time, the antidiabetic activity of G. collinum.